Configuring Port Forwarding - NETGEAR CGD24Nv2 User Manual

DOCSIS 2.0 Advanced Cable Gateway CGD24N v2 User Manual
– TCP. Select TCP only.
– UDP. Select UDP only.
– Both. Select both TCP and UDP.
• Local IP Address. Enter the local IP address for the computer that is using the service.
Note: To reset the selection in the Services pull-down menu and to clear all the fields
in the Add Custom Rules table, click Reset.
5. Perform one of the following actions:
• Click Add to save your settings. The Active Filters table now displays the list of ports that
are currently forwarded.
• To delete a service, select the radio button in the Active Filters table for the service that
you want to delete, and then click Delete.

Configuring Port Forwarding

A firewall has two default rules, one for inbound traffic (WAN to LAN) and one for outbound
traffic. Port forwarding affects the inbound rules. These rules restrict access from outsiders. The
default rule is to block all access from outside except responses to requests from the LAN side.
You can use port forwarding to add predefined or custom rules to specify exceptions to the default
rule.
Because the gateway uses Network Address Translation (NAT), your network presents only one IP
address to the Internet, and outside users cannot directly address any of your local computers.
However, by defining an inbound rule you can make a local server (for example, a web server or
game server) or computer visible and available to the Internet. The rule tells the gateway to direct
inbound traffic for a particular service to one local server or computer based on the destination port
number. This is also known as port forwarding.
Note: Some residential broadband ISP accounts do not allow you to run any server
processes (such as a web or FTP server) from your location. Your ISP may
periodically check for servers and may suspend your account if it discovers
any active services at your location. If you are unsure, refer to the Acceptable
Use Policy of your ISP.
To configure port forwarding and services for specific inbound traffic:
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v1.0, August 2009
Customizing Your Network